Minerals have many uses in Industry Technology Industry Copper Arts
Minerals have many uses in Industry Metals for cars and airplanes Quartz and feldspar for glass Fluorite and calcite for toothpaste Silver compounds for photographic film Mica and talc for paint http://dsc.discovery.com/videos/howstuffworks-the-power-of-lead.html These are just a few ways we depend on minerals.
Minerals have many uses in Art Gemstone or birth stone when first mined, gems are often rough and dull a jeweler will shape them and set them into jewelry material used to shape and polish gemstones must be as hard the gemstone itself. Gold and silver also used in jewelry other decorative arts Both combine with copper to increase hardness
Minerals are formed in several ways
Minerals are formed in several ways Water Evaporates Water usually has substances dissolved in it. Minerals can form when the water is dissolved, leaving crystals behind.
Minerals are formed in several ways Hot Water Cools As the hot water moves through the Earth it collects minerals. That hot water cools and the minerals become solid again. This process can move a mineral from one area of the Earth to another.
Minerals are formed in several ways Molten Rock Cools Magma molten rock inside the Earth contains all types of atoms that are found in minerals. as magma cools it hardens becoming solid Lava is molten rock, with minerals in it that has reached the earth's surface Quartz is a mineral that crystallizes from magma and lava
Minerals are formed in several ways Heat and Pressure Cause Changes Heat and pressure cause new minerals to form as bonds between atoms break and new ones are created At high temperatures carbon forms graphite
Minerals are formed in several ways Organisms produce minerals A few minerals are produced by living things Oysters and clams produce calcite and other carbonate minerals to form their shells. Humans produce apatite in our bones and teeth.
Many Minerals are Mined Minerals are found at Earth’s surface and deep below the Earth Most Minerals are combined with rock Ores – Rocks that contain enough mineral to be mined for profit
Many Minerals are Mined Surface Mining Minerals at or near Earth's surface are recovered by surface mining. The soil and rock covering the mineral deposits are removed. Panning Open-Pit Strip
Many Minerals are Mined Panning minerals build up in riverbeds as less dense minerals are carried away by the water Gold http://www.bbc.co.uk/news/world-europe-11808349 Open pit mining Extracting rock or minerals from the earth by their deduction from an open pit or borrows Coal, copper, gold, gravel, sand, marble
Many Minerals are Mined Strip mining miners strip away plants, soil and unwanted rocks from the surface to reach the minerals. Coal
Many Minerals are Mined Deep mining Used when ores are far below the Earth's surface Miners create an underground cave system to reach precious metals (ores) Coal, copper http://dsc.discovery.com/videos/howstuffworks-dry-salt-mining.html
Many Minerals are Mined Mining can disrupt land, air, and water systems. Because of this, there are many laws governing mining. Any estimation of the cost of mining must include the costs of exploration, excavation, environmental production during mining, and environmental reclamation afterward. These costs must be weighed against the benefits of minerals. http://www.treehugger.com/files/2010/01/scientists-say-mountaintop-removal-mining-should-be-banned.php http://video.planetgreen.discovery.com/work-connect/focus-earth-mountain-minefield.html http://www.nytimes.com/2009/01/07/us/07sludge.html?_r=2&ref=us&pagewanted=all http://video.yahoo.com/watch/4342050/11659002
Properties of Minerals We identify different minerals by certain properties they contain: Color Streak Luster Density Hardness How they break = Fracture or Cleavage
Color Minerals are colored because certain wave lengths of light are absorbed, and the color results from a combination of those wave lengths that reach the eye. For some minerals, color is directly related to one of the major elements and can be characteristic and serve as a means of identification. The color of a mineral is the first thing most people notice. But it can also be the least useful in identifying a mineral. Most minerals occur in more than one color. Ex: Fluorite can be clear, white, yellow, blue, purple, or green.
Color Examples: Malichite is always green Azurite is always blue Rhodonite is always red or pink.
Streak The streak of a mineral is the color of the powder left on a streak plate when the mineral is scraped across it. Streak Plate = piece of unglazed porcelain Only good for minerals with Hardness >7 The streak plate has a hardness of glass, so minerals with a Mohs Hardness >7 will scratch the streak plate and won't powder the mineral. Streak can be useful for identifying metallic and earthy minerals. Nonmetallic minerals usually give a white streak because they are very light-colored.
Streak Many minerals have very distinctive streaks Hematite always gives a reddish brown streak no matter what type of luster it displays. Limonite has a yellow to brown streak Graphite has a black streak (graphite is in your pencils!)
Luster How light is reflected from the surface of a mineral. The two main types of luster: Metallic = shiny like metal Nonmetallic Types of nonmetallic luster: Vitreous: The luster of glass. Resinous: The luster of resin. Pearly: The luster of pearls. Greasy: Looks like it is covered in a thin layer of oil. Silky: The luster of silk. Adamantine: A hard, brilliant luster. Translucent: You can see into the mineral, but not completely through it. Transparent: Transmits light completely through it, resembling glass.
Zircon (cubic zirconium) Diamond Luster Metallic Gold Pyrite Vitreous - Quartz Greasy - Chrysocolla Silky - Malachite Adamantine Zircon (cubic zirconium) Diamond Pearly - Talc Resinous - Amber
Hardness The hardness of a mineral is its ability to resist scratching. The hardest mineral known, diamond, was assigned the number 10. Mohs Hardness Scale ranks the order of hardness Examples: Your fingernail can scratch the minerals talc and gypsum, with a hardness of 2 or lower. A copper penny can scratch calcite, gypsum, and talc. A common misunderstanding of how to identify a diamond is that it will scratch glass. While this is true, other minerals can scratch glass, too, as long as they have a hardness >6.
Hardness: Mohs Scale
Density (Specific Gravity) How many times more the mineral weighs compared to an equal amount of water (SG 1). How hefty a specimen feels has to do with how dense it is, its mass compared to its volume
Cleavage Cleavage is when a mineral breaks with smooth flat surfaces Cleavage can be described as perfect, good, imperfect, poor.
Fracture Fracture is when a mineral breaks, but the surface is not regular, does not show cleavage
Other Properties Fluorescence Magnetism Smell Ex: Sulfer smells like rotten eggs Effervesce (fizz) with lemon juice or HCL Ex: Calcite will fizz in lemon juice Taste Ex: Halite tastes salty